fix(expect): toMatchObject(Map/Set) should expect Map/Set on left hand side
#9532
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`toMatchObject` was incorrectly passing when comparing plain objects against Map/Set because `isObjectWithKeys` didn't exclude these types. This caused `Object.keys()` to return an empty array, making `[].every()` trivially return true. Fixes vitest-dev#9522 Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
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sheremet-va
approved these changes
Jan 27, 2026
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Description
Resolves #9522
toMatchObjectwas loose sincesubsetEqualitytreats Map/Set as empty object. This feels like an unexpected behavior since builtiniterableEqualityis already aware ofMap/Setand for example,toMatchObjectsupports deeply asserting shapes whenMap/Setappears at the same nested level (so,subset equality works inside Set/Maptest added here already passes before this PR).I found there is also relatively recent change on Jest jestjs/jest#14873 jestjs/jest#14599, which get addressed with same fix.
Please don't delete this checklist! Before submitting the PR, please make sure you do the following:
pnpm-lock.yamlunless you introduce a new test example.Tests
pnpm test:ci.Documentation
pnpm run docscommand.Changesets
feat:,fix:,perf:,docs:, orchore:.